Abstract-The problem of computing a route for a mobile agent that incrementally fuses the data as it visits the nodes in a distributed sensor network is considered. The order of nodes visited along the route has a significant impact on the quality and cost of fused data, which, in turn, impacts the main objective of the sensor network, such as target classification or tracking. We present a simplified analytical model for a distributed sensor network and formulate the route computation problem in terms of maximizing an objective function, which is directly proportional to the received signal strength and inversely proportional to the path loss and energy consumption. We show this problem to be NP-complete and propose a genetic algorithm to compute an approximate solution by suitably employing a two-level encoding scheme and genetic operators tailored to the objective function. We present simulation results for networks with different node sizes and sensor distributions, which demonstrate the superior performance of our algorithm over two existing heuristics, namely, local closest first and global closest first methods.

UltraScienceNet is an experimental wide-area network testbed to enable the development of networking technologies required for the next-generation large-scale scientific applications. It provides on-demand, dedicated, high bandwidth channels for large data transfers, and also high resolution, high-precision channels for fine control operations. In the initial deployment, its data-plane consists of several thousand miles of dual 10 Gbps lambdas. The channels are provisioned on-demand using layer-1 and layer-2 switches in the backbone and multiple service provisioning platforms at the edges in a flexible configuration using a secure control-plane. A centralized scheduler is employed to compute the future channel allocations, and a signaling daemon is used to generate the configuration signals to switches at appropriate times. The control-plane is implemented using an out-of-band virtual private network, which encrypts the switching signals and also provides authenticated user and application access. Transport experiments are conducted on a smaller test connection which provided us useful information about the basic properties and issues of utilizing dedicated channels in applications.Index Terms-Network testbed, dedicated channels, SONET, 10GigE WAN-PHY, control-plane, data-plane, bandwidth scheduler.

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Abstract-Identification of a low-level point radiation source amidst background radiation is achieved by a network of radiation sensors using a two-step approach. Based on measurements from three sensors, the geometric difference triangulation method is used to estimate the location and strength of the source. Then a sequential probability ratio test based on current measurements and estimated parameters is employed to finally decide: (i) presence of a source with the estimated parameters, or (ii) absence of the source, or (iii) insufficiency of measurements to make a decision. This method achieves the specified levels of false alarm and missed detection probabilities, while ensuring close to minimal number of measurements to reach a decision. This method minimizes the ghost-source problem of the current estimation methods and achieves lower false alarm rate compared to current detection methods. This method is tested and demonstrated using: (a) simulations, and (b) a test-bed that utilizes the scaling properties of point radiation sources to emulate high intensity ones that cannot be easily and safely handled in experimentation.

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